Commit Graph

6068 Commits

Author SHA1 Message Date
Rafael Espindola d39dadeb64 Don't produce a relocation to read only memory.
This is hopefully last case where we would produce a relocation to a
read only section.

llvm-svn: 268688
2016-05-05 21:19:38 +00:00
Rafael Espindola 66434562e7 Fix copy relocations in pie.
We were creating the copy relocations just fine, but then thinking that
the .bss position could be preempted and creating a dynamic relocation
to it, which would crash at runtime since that memory is read only.

llvm-svn: 268668
2016-05-05 19:41:49 +00:00
Peter Collingbourne 3ad1c1e242 ELF: Undefine all symbols, not just those that we expect to be defined.
This allows the combined LTO object to provide a definition with the same
name as a symbol that was internalized without causing a duplicate symbol
error. This normally happens during parallel codegen which externalizes
originally-internal symbols, for example.

In order to make this work, I needed to relax the undefined symbol error to
only report an error for symbols that are used in regular objects.

Differential Revision: http://reviews.llvm.org/D19954

llvm-svn: 268649
2016-05-05 17:13:49 +00:00
Rafael Espindola 474eb019b4 Move static function to avoid forward declaration. NFC.
llvm-svn: 268646
2016-05-05 16:40:28 +00:00
Rafael Espindola 462220de47 Reuse logic for deciding whether to keep a local symbol or not.
llvm-svn: 268644
2016-05-05 16:38:46 +00:00
Rafael Espindola 3e0b7837bf Cache result when tail merging too.
This speeds up a link of chromium with -O2 (but no icf,gc) from
1.940664632 to 1.925578119.

llvm-svn: 268639
2016-05-05 16:12:25 +00:00
Rafael Espindola d89fbca21d Fix --gc-sections when .eh_frame has a lsda.
We have to add sections to the work list, not just mark them live.

llvm-svn: 268628
2016-05-05 13:51:14 +00:00
Peter Collingbourne e29e142a10 ELF: Do not use -1 to mark pieces of merge sections as being tail merged.
We were previously using an output offset of -1 for both GC'd and tail
merged pieces. We need to distinguish these two cases in order to filter
GC'd symbols from the symbol table -- we were previously asserting when we
asked for the VA of a symbol pointing into a dead piece, which would end
up asking the tail merging string table for an offset even though we hadn't
initialized it properly.

This patch fixes the bug by using an offset of -1 to exclusively mean GC'd
pieces, using 0 for tail merges, and distinguishing the tail merge case from
an offset of 0 by asking the output section whether it is tail merge.

Differential Revision: http://reviews.llvm.org/D19953

llvm-svn: 268604
2016-05-05 04:10:12 +00:00
Rui Ueyama ca16c104c6 Merge two tests for the same purpose.
I accidentally added another test file as I didn't notice
that the test file existed.

llvm-svn: 268598
2016-05-05 02:32:09 +00:00
Rui Ueyama ac75a27809 Add a test for --reproduce on Windows.
It is insanely hard to write a test that works both on Windows and Unix.
I tried to workaround it with cpio's minor options, but the behaviors of
the options were myterious. It just doesn't worth to spend time on it.
And probably minor options could break buildbots that doesn't have the
GNU version of cpio command.

In this patch, I simply added a separate test file that runs only on
Windows.

llvm-svn: 268596
2016-05-05 02:18:04 +00:00
Rui Ueyama af2312feb7 Make --reproduce to not produce undesired whitespace.
Fixes bug 27648.

llvm-svn: 268569
2016-05-04 23:12:55 +00:00
Simon Atanasyan da83bbc1a1 [ELF][MIPS] Create combined dynamic relocation type R_MIPS_REL32/R_MIPS_64/R_MIPS_NONE
MIPS N64 ABI packs multiple relocations into the single relocation
record. Particularly it requires to represent dynamic relative
relocation as a combination of R_MIPS_REL32 and R_MIPS_64 relocations.

llvm-svn: 268565
2016-05-04 22:39:40 +00:00
Rafael Espindola de17d28a32 Don't produce relative relocs to ro segments.
We were already checking for non relative relocations.

If we ever decide to add support for rw text segments this means we will
have a single spot to add the flag.

llvm-svn: 268558
2016-05-04 21:40:07 +00:00
Rafael Espindola 3fa5bbd91b Rename isRelRelative.
What it is computing is if we need a dynamic relocation or not.

llvm-svn: 268556
2016-05-04 21:28:56 +00:00
Rafael Espindola 946ca27b61 Use early return. NFC.
llvm-svn: 268554
2016-05-04 21:09:24 +00:00
Rui Ueyama 0cfed297de Handle errors on file opening as soft error.
Also improves the error message. Previously it would just print out
the cause (e.g. "permission denied"). Now it prints out something like
"--reproduce: failed to open foo.cpio: permission denied".

llvm-svn: 268551
2016-05-04 21:05:11 +00:00
Rafael Espindola ac95264d62 Don't depend on dynamic relocatinos in ro sections.
Currently we don't check when creating relative relocations if the
section is read only or not. I am about to fix that, so first update the
patches that depend on the current behavior.

llvm-svn: 268542
2016-05-04 20:25:19 +00:00
Rafael Espindola 1bf2f191b6 Split a testcase.
I will make changes to the -shared side and this reduces the noise in
the other patch.

llvm-svn: 268538
2016-05-04 20:06:49 +00:00
Simon Atanasyan be804559f8 [ELF][MIPS] R_MIPS_GOT_DISP, R_MIPS_GOT_PAGE, R_MIPS_GOT_OFST relocations support
These relocations introduced by MIPS N64 ABI. R_MIPS_GOT_DISP references
GOT entry with full symbol's address, R_MIPS_GOT_PAGE creates GOT entry
with address of memory page which includes symbol's address,
R_MIPS_GOT_OFST used together with R_MIPS_GOT_PAGE. This relocation
calculates offset from beginning of memory page to the symbol address.

llvm-svn: 268525
2016-05-04 17:47:11 +00:00
Rafael Espindola 38bd217d0c Delete getTlsGotRel.
It was an old hack to avoid duplicating expression computation, but that
is not needed with getExprRel.

llvm-svn: 268515
2016-05-04 15:51:23 +00:00
George Rimar 5ed31e2f58 Removed another dead code. NFC.
llvm-svn: 268505
2016-05-04 15:04:08 +00:00
Rafael Espindola ebb04b9eb6 Simplify handling of hint relocations.
llvm-svn: 268501
2016-05-04 14:44:22 +00:00
Rafael Espindola de2c76ed73 Sort entries. NFC.
llvm-svn: 268499
2016-05-04 14:38:55 +00:00
George Rimar fbfe10f221 Removed dead code. NFC.
llvm-svn: 268497
2016-05-04 13:44:49 +00:00
Daniel Sanders c07f06aeee [mips][ias] Only round section sizes when explicitly requested.
As requested by Rafael Espindola in his post-commit comments on r268036. This
makes the previous behaviour the default while still allowing verification of
IAS.

llvm-svn: 268496
2016-05-04 13:21:06 +00:00
Rafael Espindola 2c51e619d5 Print the cpio trailer after every member.
This is both simpler and safer. If we crash at any point, there is a
valid cpio file to reproduce the crash.

Thanks to Rui for the suggestion.

llvm-svn: 268495
2016-05-04 12:47:56 +00:00
Simon Atanasyan 5e85a1b5be [ELF][MIPS] Fix typo in the comment. NFC.
llvm-svn: 268486
2016-05-04 10:15:12 +00:00
Simon Atanasyan add74f37f2 [ELF][MIPS] Read/write .MIPS.options section
MIPS N64 ABI introduces .MIPS.options section which specifies miscellaneous
options to be applied to an object/shared/executable file. LLVM as well as
modern versions of GNU tools read and write the only type of the options -
ODK_REGINFO. It is exact copy of .reginfo section used by O32 ABI.

llvm-svn: 268485
2016-05-04 10:07:38 +00:00
Rafael Espindola c5b8ed241d Implement --build-id=none.
Both bfd and gold have this. It allows disabling build-id when it is the
default with by adding -Wl,--build-id=none no the clang command line.

llvm-svn: 268435
2016-05-03 20:55:47 +00:00
Peter Collingbourne f3a2b0e8f7 ELF: Fix regression in TLS attribute mismatch logic.
Introduce a special symbol type to indicate that we have not yet seen a type
for the symbol, so we should not report TLS mismatches for that symbol.

Differential Revision: http://reviews.llvm.org/D19836

llvm-svn: 268411
2016-05-03 18:03:47 +00:00
Peter Collingbourne 6f535b744f Check return value of addOptionalSynthetic before calling a member function on it.
Found with UBSan.

llvm-svn: 268410
2016-05-03 18:03:45 +00:00
Rafael Espindola 1dd2b3d1d0 Produce cpio files for --reproduce.
We want --reproduce to

* not rewrite scripts and thin archives
* work with absolute paths

Given that, it pretty much has to create a full directory tree. On windows that
is problematic because of the very short maximum path limit. On most cases
users can still work around it with "--repro c:\r", but that is annoying and
not viable for automated testing.

We then need to produce some form of archive with the files. The first option
that comes to mind is .a files since we already have code for writing them.
There are a few problems with them

The format has a dedicated string table, so we cannot start writing it until
all members are known.
Regular implementations don't support creating directories. We could make
llvm-ar support that, but that is probably not a good idea.
The next natural option would be tar. The problem is that to support long path
names (which is how this started) it needs a "pax extended header" making this
an annoying format to write.

The next option I looked at seems a natural fit: cpio files.

They are available on pretty much every unix, support directories and long path
names and are really easy to write. The only slightly annoying part is a
terminator, but at least gnu cpio only prints a warning if it is missing, which
is handy for crashes. This patch still makes an effort to always create it.

llvm-svn: 268404
2016-05-03 17:30:44 +00:00
Rafael Espindola d8dfdfd268 Don't depend on checking the response file when lld fails.
llvm-svn: 268388
2016-05-03 14:29:42 +00:00
Rafael Espindola 630ccd6a3f Remove unused includes.
llvm-svn: 268381
2016-05-03 13:57:49 +00:00
Peter Collingbourne c357278a38 ELF: Remove the function SymbolTable<ELFT>::findFile.
We already have the function SymbolBody::getSourceFile which does the same thing.

llvm-svn: 268353
2016-05-03 01:48:25 +00:00
Sean Silva 92fbd8df15 Try harder to get the bots green.
The test is now unexpectedly passing on
llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast which is treated as an error.
For now, disable Windows testing of the feature.
Rafael is working on generating an archive, which will hopefully allow
us to turn this test back on.

Unfortunately, we don't have a way to temporarily XFAIL this test just
on llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast.

llvm-svn: 268351
2016-05-03 01:25:28 +00:00
Peter Collingbourne 6a4225962d ELF: Forbid all relative relocations to absolute symbols in PIC, except for weak undefined.
Weak undefined symbols resolve to the image base. This is a little strange,
but it allows us to link function calls to such symbols. Normally such a
call will be guarded with a comparison, which will load a zero from the GOT.

There's one example of such a function call in crti.o in Linux's CRT.

As part of this change, I also needed to make the synthetic start and end
symbols image base relative in the case where their sections were empty,
so that PC-relative references to those symbols would continue to work.

Differential Revision: http://reviews.llvm.org/D19844

llvm-svn: 268350
2016-05-03 01:21:08 +00:00
Sean Silva 2b34def662 Temporarily disable this test on llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast
`REQUIRES: shell` is not appropriate because that would mean that there
are no windows bots testing this, and that is precisely where it needs
the most testing.

Rafael or Rui are working on generating an archive directly, which
should avoid this issue.
We can try to move the bot to a shorter build directory path.

llvm-svn: 268345
2016-05-03 00:36:15 +00:00
Rui Ueyama dd368fcb05 Pass all buffers to BuildId hash function at once. NFC.
This change simplifies the BuildId classes by removing a few member
functions and variables from them. It should also make it easy to
parallelize hash computation in future because now each BuildId object
see all inputs rather than one at a time.

llvm-svn: 268333
2016-05-02 23:35:59 +00:00
Rafael Espindola 133ebe5bc7 Simplify. NFC.
llvm-svn: 268324
2016-05-02 22:52:15 +00:00
Rui Ueyama 6d0cd2b62b Teach Undefined symbols from which file they are created from.
This patch increases the size of Undefined by the size of a pointer,
but it wouldn't actually increase the size of memory that LLD uses
because we are not allocating the exact size but the size of the
largest SymbolBody.

llvm-svn: 268310
2016-05-02 21:30:42 +00:00
Rafael Espindola 6bbd78df6f Revert "Temporary hack to see what is going on on a windows bot."
This reverts commit r268302.

llvm-svn: 268308
2016-05-02 21:21:26 +00:00
Rafael Espindola 732c4646ee Temporary hack to see what is going on on a windows bot.
llvm-svn: 268302
2016-05-02 20:47:06 +00:00
Rui Ueyama 5002a67ef2 Remove unnecessary namespace specifiers.
llvm-svn: 268292
2016-05-02 19:59:56 +00:00
Rui Ueyama 4f8d21f387 Do not pass Symtab to markLive/doICF since Symtab is globally accessible.
llvm-svn: 268286
2016-05-02 19:30:42 +00:00
Rui Ueyama fc28827216 Remove unnecessary namespace specifiers.
llvm-svn: 268278
2016-05-02 18:51:08 +00:00
Rui Ueyama ff12f23080 Attempt to fix Windows bots.
llvm-svn: 268275
2016-05-02 18:16:14 +00:00
Rui Ueyama 2664d45267 Fix --reproduce for --export-dynamic-symbol.
--export-dynamic-symbol doesn't take path.

llvm-svn: 268273
2016-05-02 18:12:09 +00:00
Rui Ueyama e951a1d739 Quote arguments for --reproduce.
llvm-svn: 268258
2016-05-02 17:34:17 +00:00
Rafael Espindola 2076567be4 Force llvm-ar to use the gnu format.
Should fix the bots. Otherwise we try to create a thin bsd anchive.

llvm-svn: 268240
2016-05-02 15:16:43 +00:00
Rafael Espindola e85bcbd1c3 Don't include the output dir in the response file.
With this it is possible to use chroot/fakechroot to have a completely
reproducible link even when thin archives or linker scripts have
absolute paths.

llvm-svn: 268231
2016-05-02 14:12:35 +00:00
Rafael Espindola d1cbe4df91 Copy thin archive members with --reproduce.
llvm-svn: 268229
2016-05-02 13:54:10 +00:00
George Rimar af90d54660 [ELF] - keep alive all non-text sections referenced by .eh_frame
Patch implements one of suggestions from Rafael Ávila de Espíndola,
to fix segfault after section that contains personality being
garbage collected.

Suggestion was just to keep alive all non executable sections
referenced by .eh_frame.

This fixes PR27529.

Differential revision: http://reviews.llvm.org/D19656

llvm-svn: 268228
2016-05-02 13:49:42 +00:00
Rafael Espindola 21e1489048 Don't quote "--hash-style gnu".
Otherwise lld fails to use the response file.

llvm-svn: 268225
2016-05-02 13:00:42 +00:00
Simon Atanasyan 63dcba05b7 Replace non-ascii character.
llvm-svn: 268218
2016-05-02 09:49:03 +00:00
Peter Collingbourne 3db410e865 Should fix all remaining MSVC problems.
llvm-svn: 268187
2016-05-01 06:00:09 +00:00
Peter Collingbourne f643fc10d1 Further MSVC appeasement.
llvm-svn: 268185
2016-05-01 05:39:02 +00:00
Peter Collingbourne 6e862bbfa3 Try to fix MSVC build.
llvm-svn: 268182
2016-05-01 05:12:13 +00:00
Peter Collingbourne 4f9527065c ELF: New symbol table design.
This patch implements a new design for the symbol table that stores
SymbolBodies within a memory region of the Symbol object. Symbols are mutated
by constructing SymbolBodies in place over existing SymbolBodies, rather
than by mutating pointers. As mentioned in the initial proposal [1], this
memory layout helps reduce the cache miss rate by improving memory locality.

Performance numbers:

           old(s) new(s)
Without debug info:
chrome      7.178  6.432 (-11.5%)
LLVMgold.so 0.505  0.502 (-0.5%)
clang       0.954  0.827 (-15.4%)
llvm-as     0.052  0.045 (-15.5%)
With debug info:
scylla      5.695  5.613 (-1.5%)
clang      14.396 14.143 (-1.8%)

Performance counter results show that the fewer required indirections is
indeed the cause of the improved performance. For example, when linking
chrome, stalled cycles decreases from 14,556,444,002 to 12,959,238,310, and
instructions per cycle increases from 0.78 to 0.83. We are also executing
many fewer instructions (15,516,401,933 down to 15,002,434,310), probably
because we spend less time allocating SymbolBodies.

The new mechanism by which symbols are added to the symbol table is by calling
add* functions on the SymbolTable.

In this patch, I handle local symbols by storing them inside "unparented"
SymbolBodies. This is suboptimal, but if we do want to try to avoid allocating
these SymbolBodies, we can probably do that separately.

I also removed a few members from the SymbolBody class that were only being
used to pass information from the input file to the symbol table.

This patch implements the new design for the ELF linker only. I intend to
prepare a similar patch for the COFF linker.

[1] http://lists.llvm.org/pipermail/llvm-dev/2016-April/098832.html

Differential Revision: http://reviews.llvm.org/D19752

llvm-svn: 268178
2016-05-01 04:55:03 +00:00
Rui Ueyama 2796ae3f69 ELF: --reproduce: quote pathnames for -L and other options.
Previously, arguments for options that take pathnames were not rewritten.

llvm-svn: 268172
2016-04-30 22:46:47 +00:00
Rui Ueyama 9aea957f6d ELF: --reproduce: Copy files referenced by linker scripts.
Previuosly, only files appeared on the command line were copied.

llvm-svn: 268171
2016-04-30 22:23:29 +00:00
Rui Ueyama 38aa57d966 Attempt to fix Windows buildbots.
llvm-svn: 268170
2016-04-30 22:20:27 +00:00
Rui Ueyama aa00e96a84 ELF: Make --reproduce to produce a response file.
The aim of this patch is to make it easy to re-run the command without
updating paths in the command line. Here is a use case.

Assume that Alice is having an issue with lld and is reporting the issue
to developer Bob. Alice's current directly is /home/alice/work and her
command line is "ld.lld -o foo foo.o ../bar.o". She adds "--reproduce repro"
to the command line and re-run. Then the following text will be produced as
response.txt (notice that the paths are rewritten so that they are
relative to /home/alice/work/repro.)

  -o home/alice/work/foo home/alice/work/foo.o home/alice/bar.o

The command also produces the following files by copying inputs.

  /home/alice/repro/home/alice/work/foo.o
  /home/alice/repro/home/alice/bar.o

Alice zips the directory and send it to Bob. Bob get an archive from Alice
and extract it to his home directory as /home/bob/repro. Now his directory
have the following files.

  /home/bob/repro/response.txt
  /home/bob/repro/home/alice/work/foo.o
  /home/bob/repro/home/alice/bar.o

Bob then re-run the command with these files by the following commands.

  cd /home/bob/repro
  ld.lld @response.txt

This command will run the linker with the same command line options and
the same input files as Alice's, so it is very likely that Bob will see
the same issue as Alice saw.

Differential Revision: http://reviews.llvm.org/D19737

llvm-svn: 268169
2016-04-30 21:40:04 +00:00
Rafael Espindola a85efd985c Don't create dynamic relocations to ro segments.
These would just crash at runtime.

If we ever decide to support rw text segments this should make it easier
to implement as there is now a single point where we notice the problem.

I have tested this with a freebsd buildworld. It found a non pic
assembly file being linked into a .so,. With that fixed, buildworld
finished.

llvm-svn: 268149
2016-04-30 01:15:17 +00:00
Rafael Espindola cceacd7113 Don't depend on lld creating relocations in ro segments.
We currently don't do a good job of diagnosing inputs that would require
dynamic relocations to be applied to read only segments.

I am about to improve lld in that area, but unfortunately we developed
tests that depend on the current behavior.

To make clear what is actually changing, this first patch just updates
tests to not depend on the current behavior. In most cases this just
means using a rw section instead of a ro one, but that unfortunately
changes many addresses.

llvm-svn: 268145
2016-04-30 00:49:10 +00:00
Rafael Espindola f1e880eb8d Document how to recreate a binary.
llvm-svn: 268136
2016-04-29 23:35:49 +00:00
Rafael Espindola 9e5e2df3f3 Document how to recreate a binary.
llvm-svn: 268134
2016-04-29 23:28:36 +00:00
Rafael Espindola aae59561d6 Use simpler types. NFC.
llvm-svn: 268133
2016-04-29 23:20:30 +00:00
Davide Italiano bf5ef7b63b [ELF] Ignore -d option (and aliases).
The linker already allocates common symbols by default.
Discussed with Rafael.

llvm-svn: 268117
2016-04-29 21:44:02 +00:00
Eugene Zelenko 20a38451f5 Fix some Include What You Use warnings; other minor fixes.
Differential revision: http://reviews.llvm.org/D19735

llvm-svn: 268093
2016-04-29 19:47:09 +00:00
Rui Ueyama d74ce4d393 Fix typo in test.
llvm-svn: 268080
2016-04-29 17:58:48 +00:00
Rafael Espindola fb4f2fedd1 Be sure to always increment the Versym pointer.
It was getting out of sync if we had undefined symbols at the start of
the symbol table.

llvm-svn: 268077
2016-04-29 17:46:07 +00:00
Rafael Espindola eaaec4a4c8 Fix the alignment of the version info.
llvm-svn: 268070
2016-04-29 17:19:45 +00:00
Rafael Espindola 18da0e589a Fix producing undefined reference to __progname.
We were not producing them if the library had version info.

llvm-svn: 268060
2016-04-29 16:23:31 +00:00
Rui Ueyama fb6d499ed7 ELF: Add -O0 (produce output as fast as possible) mode.
This patch redefines the default optimization level as 1 and adds
new level 0. In the command line, it is -O0. The flag disables
costly but optional features so that the linker produces semantically
correct but larger output quickly. Currently it only disables
section merging.

This flag is not intended to be used for final production linking.
It is intended to be used in compile-link-test cycle.

Time to link clang with debug info is about 2x faster with the flag.

  Head:
  13.24 seconds
  Output size: 1227189664 bytes

  With this patch:
  7.41 seconds
  Output size: 2490281784 bytes

Differential Revision: http://reviews.llvm.org/D19705

llvm-svn: 268056
2016-04-29 16:12:29 +00:00
George Rimar 9fc5908674 [ELF] Fixed warning. NFC.
SymbolTable.cpp:298:36: warning: enumeral and non-enumeral type in conditional expression [-Wextra]
     Sym->Binding = New->isShared() ? STB_GLOBAL : New->Binding;
                                    ^

llvm-svn: 268040
2016-04-29 13:32:30 +00:00
Daniel Sanders 2c83917c42 [mips] Update tests to account for section size rounding change in r268036.
llvm-svn: 268039
2016-04-29 13:21:26 +00:00
Simon Atanasyan ae77ab71d8 [ELF][MIPS] Accept MIPS 64-bit binaries
LLD accepts MIPS 64-bit binaries, supports corresponding eulation (-m)
arguments and emits 64-bit specific ELF flags.

llvm-svn: 268024
2016-04-29 10:39:17 +00:00
Rui Ueyama 890ce0c188 Do not produce broken debug info.
r267917 produces corrupted debug info because it didn't apply
relocations to right offsets.

llvm-svn: 267979
2016-04-29 03:21:08 +00:00
Rafael Espindola 0de48c393d Delete dead variable.
llvm-svn: 267935
2016-04-28 20:29:12 +00:00
Rafael Espindola 156f4ee1c0 Use a single context for lto.
Using multiple context used to be a really big memory saving because we
could free memory from each file while the linker proceeded with the
symbol resolution. We are getting lazier about reading data from the
bitcode, so I was curious if this was still a good tradeoff.

One thing that is a bit annoying is that we still have to copy the
symbol names. The problem is that the names are stored in the Module and
get freed when we move the module bits during linking.

Long term I think the solution is to add a symbol table to the bitcode.
That way IRObject file will not need to use a Module or a Context and we
can drop it while still keeping a StringRef to the names.

This patch is still be an interesting medium term improvement.

When linking llvm-as without debug info this patch is a small speedup:

master: 29.861877513 seconds
patch: 29.814533787 seconds

With debug info the numbers are

master: 34.765181469 seconds
patch: 34.563351584 seconds

The peak memory usage when linking llvm-as with debug info was

master: 599.10MB
patch: 600.13MB
llvm-svn: 267921
2016-04-28 19:30:41 +00:00
Rui Ueyama 2b6fb80384 Skip scanRelocs for non-alloc sections.
Relocations against sections with no SHF_ALLOC bit are R_ABS relocations.
Currently we are creating Relocations vector for them, but that is wasteful.
This patch is to skip vector construction and to directly apply relocations
in place.

This patch seems to be pretty effective for large executables with debug info.
r266158 (Rafael's patch to change the way how we apply relocations) caused a
temporary performance degradation for such executables, but this patch makes
it even faster than before.

Time to link clang with debug info (output size is 1070 MB):

  before r266158: 15.312 seconds (0%)
  r266158:        17.301 seconds (+13.0%)
  Head:           16.484 seconds (+7.7%)
  w/patch:        13.166 seconds (-14.0%)

Differential Revision: http://reviews.llvm.org/D19645

llvm-svn: 267917
2016-04-28 18:42:04 +00:00
Rafael Espindola b8ff59ac12 Rename isRelRelative
It was never a particularly good name and is now completely out of date.

llvm-svn: 267886
2016-04-28 14:34:39 +00:00
Rafael Espindola fbb18fb6b9 Add a test showing that we can gc parts of .eh_frame.
llvm-svn: 267884
2016-04-28 14:31:09 +00:00
George Rimar 959d180fa6 Fixed mistype in comment. NFC.
llvm-svn: 267878
2016-04-28 13:38:10 +00:00
Rui Ueyama e5c1ec4716 Add comment.
llvm-svn: 267847
2016-04-28 03:04:15 +00:00
Rui Ueyama 5d7a3d011d Do not call hasArg and getLastArg for the same option.
llvm-svn: 267839
2016-04-28 02:08:54 +00:00
Rui Ueyama 62ee16faa8 Remove Size from Undefined symbol.
There seems to be no reason to keep st_size of undefined symbols.
This patch removes the member for it. This patch will change outputs
in cases that undefined symbols are copied to output, but I think
this is unimportant.

Differential Revision: http://reviews.llvm.org/D19574

llvm-svn: 267826
2016-04-28 00:26:54 +00:00
Rui Ueyama 1b70d666ae Do not lookup the symbol table twice for each --wrap.
llvm-svn: 267822
2016-04-28 00:03:38 +00:00
Rafael Espindola 9fdd071d01 Sort includes. NFC.
llvm-svn: 267821
2016-04-27 23:54:04 +00:00
Davide Italiano 575ad8c2e1 [ELF] -R is an alias for -rpath.
perl-5 uses the former, so provide an alias. Found while linking
the whole set of FreeBSD ports with lld.

llvm-svn: 267801
2016-04-27 21:56:53 +00:00
Peter Collingbourne 21a12fc69a ELF: Create .gnu.version and .gnu.version_r sections when linking against versioned DSOs.
Differential Revision: http://reviews.llvm.org/D19464

llvm-svn: 267775
2016-04-27 20:22:31 +00:00
Rafael Espindola 7ac9628648 Reduce usage of isRelRelative.
It is now used only for relocations that only set the low bits inside a
page. Everything else is handled by getRelExpr.

I will send a another review renaming and better documenting
isRelRelative.

llvm-svn: 267705
2016-04-27 12:47:30 +00:00
Rafael Espindola 15cec298e6 Represent TOC relative relocations as GOTREL.
That way we only need to subtract the offset is relocateOne.

llvm-svn: 267702
2016-04-27 12:25:22 +00:00
Rafael Espindola 520ed3a621 Create a .got when PPC64 uses a TOC.
This simplifies the logic for computing the value of the toc base.

llvm-svn: 267701
2016-04-27 12:21:27 +00:00
Rafael Espindola 365e5f69c9 Simplify handling of R_PPC64_TOC. NFC.
llvm-svn: 267698
2016-04-27 11:54:07 +00:00
George Rimar 22a95121b9 Removed dead code. NFC.
llvm-svn: 267685
2016-04-27 09:24:03 +00:00
George Rimar 5f85732738 [ELF] - Align sections file offsets correctly.
System V ABI 4.1 specifies that program header's p_vaddr should equal p_offset, modulo p_align. 
(https://docs.oracle.com/cd/E19683-01/816-1386/chapter6-83432/index.html).
It was possible to violate this using the linkerscript.
Patch fixes the issue.

Differential revision: http://reviews.llvm.org/D19416

llvm-svn: 267684
2016-04-27 09:16:28 +00:00
Simon Atanasyan 4ee2918e6e [ELF][MIPS] Remove getMipsGpAddr(). NFC
llvm-svn: 267673
2016-04-27 05:31:28 +00:00
Rui Ueyama 389aa8e91e Simplify. NFC.
llvm-svn: 267663
2016-04-27 03:04:56 +00:00
Rui Ueyama 144debcc0f Remove unnecessary trailing semicolons.
Since this semicolon existed in an early test file,
it has spread to many files.

llvm-svn: 267659
2016-04-27 02:58:27 +00:00
Peter Collingbourne 60976ed7c0 ELF: Merge UndefinedBitcode and UndefinedElf. NFC.
Differential Revision: http://reviews.llvm.org/D19566

llvm-svn: 267640
2016-04-27 00:05:06 +00:00
Peter Collingbourne 892d498017 ELF: Re-implement -u directly and remove CanKeepUndefined flag.
The semantics of the -u flag are to load the lazy symbol named by the flag. We
were previously relying on this behavior falling out of symbol resolution
against a synthetic undefined symbol, but that didn't quite give us the
correct behavior, so we needed a flag to mark symbols created with -u so
we could treat them specially in the writer. However, it's simpler and less
error prone to implement the required behavior directly and remove the flag.

This fixes an issue where symbols loaded with -u would receive hidden
visibility even when the definition in an object file had wider visibility.

Differential Revision: http://reviews.llvm.org/D19560

llvm-svn: 267639
2016-04-27 00:05:03 +00:00
Peter Collingbourne 676c7cd1ed ELF: Move code to where it is used, and related cleanups. NFC.
Differential Revision: http://reviews.llvm.org/D19490

llvm-svn: 267637
2016-04-26 23:52:44 +00:00
Rafael Espindola 1763dc44b9 Return R_GOTREL for R_MIPS_GPREL*.
This lets Writer.cpp know that they are got relative, which will allow
further simplifications.

llvm-svn: 267613
2016-04-26 22:00:04 +00:00
Rafael Espindola 6c75238aca Call repl in getSymbolBody. NFC.
Every caller was doing it.

llvm-svn: 267603
2016-04-26 20:45:31 +00:00
Rui Ueyama cf0dd1ebf2 Move utility functions to DriverUtils.cpp.
llvm-svn: 267602
2016-04-26 20:41:32 +00:00
Rui Ueyama 673b609586 Handle Windows drive letters and ".." for --reproduce.
When --reproduce <path> is given, then we need to concatenate input
file paths to the given path to save input files to the directory.
Previously, path concatenation didn't handle Windows drive letters
so it could generate invalid paths such as "C:\D:\foo". It also didn't
handle ".." path components, so it could produce some bad paths
such as "foo/../../etc/passwd".

In this patch, Windows drive letters and ".." are removed before
concatenating paths.

Differential Revision: http://reviews.llvm.org/D19551

llvm-svn: 267600
2016-04-26 20:36:46 +00:00
Rui Ueyama 3578d334fb Make test/ELF/reproduces.s test to work on Windows.
Previously, the test didn't work on Windows because it tried to
concatenate two (possibly) absolute paths. If two paths are absolute
paths that have drive letters, then the result would become something
like C:\foo\D:\bar. That's not a valid path. I changed the test to
use relative paths.

llvm-svn: 267588
2016-04-26 19:04:35 +00:00
Peter Collingbourne dbcf5b99d0 Remove unnecessary function type directives for ifuncs.
llvm-svn: 267569
2016-04-26 16:50:02 +00:00
Rafael Espindola 1b65ad1725 Don't gc symbols that have to go in the dynamic symbol table.
We were only doing it for .so and --export-dynamic, but those are not
the only ways a symbol ends up in the dynamic symbol table.

Problem diagnostic and earlier patch version by Peter Collingbourne.

llvm-svn: 267568
2016-04-26 16:26:45 +00:00
Peter Collingbourne 5dd550a3ff ELF: Treat IFunc definitions in DSOs as functions.
Differential Revision: http://reviews.llvm.org/D19517

llvm-svn: 267566
2016-04-26 16:22:51 +00:00
Davide Italiano 366290bb26 [ELF] Avoid polluting source directory with temp files.
llvm-svn: 267565
2016-04-26 16:21:59 +00:00
Rafael Espindola 0baa73f317 Handle --as-needed with symbols, not relocations.
This matches the behavior of both gold and bfd.

llvm-svn: 267558
2016-04-26 13:56:26 +00:00
Rafael Espindola 9e32e4fe86 Store the binding in the Symbol.
This remove a fixme, cleans up the weak undef interaction with archives and
lets us keep weak undefs still weak if they resolve to shared.

llvm-svn: 267555
2016-04-26 13:50:46 +00:00
Davide Italiano e53e6e9f37 [ELF] Simplify. Pointed out by Rui Ueyama.
llvm-svn: 267523
2016-04-26 05:51:37 +00:00
Davide Italiano 957d084811 [Tests] Run reproduces.s only on UNIX until I investigate a windows failure.
llvm-svn: 267505
2016-04-26 00:56:19 +00:00
Davide Italiano 034f58a9bd [ELF] Introduce --reproduce flag.
--reproduce dumps the object files in a directory chosen
(preserving the file system layout) and the linker invocation
so that people can create an archive and upload for debugging.

Differential Revision:  http://reviews.llvm.org/D19494

llvm-svn: 267497
2016-04-26 00:22:24 +00:00
Simon Atanasyan 1ef1bf87dc [ELF][MIPS] Move MIPS GOT header generation to the GotSection
MIPS is the only target requires GOT header. We already have MIPS
specific code in the `GotSection` class, so move MIPS GOT header
generation there and delete redundant stuff like `GotHeaderEntriesNum`
field and `writeGotHeader` method.

Differential Revision: http://reviews.llvm.org/D19465

llvm-svn: 267460
2016-04-25 20:25:05 +00:00
Rafael Espindola 926bff8c3e Add support for R_X86_64_PC64.
llvm-svn: 267409
2016-04-25 14:05:44 +00:00
Rafael Espindola d79073dc2a Simplify. NFC.
llvm-svn: 267396
2016-04-25 12:32:19 +00:00
Rafael Espindola a6c4d2f197 Delete needsCopyRelImpl. It is redundant with getRelExpr.
llvm-svn: 267394
2016-04-25 12:05:56 +00:00
Simon Atanasyan c245d84213 [ELF] Delete extra line. NFC
llvm-svn: 267391
2016-04-25 10:18:48 +00:00
George Rimar ab9390664f [ELF] - Implemented comparsion operators for linkerscript.
Patch adds support of <,>,!=,==,>=,<= operators.

Differential revision: http://reviews.llvm.org/D19419

llvm-svn: 267382
2016-04-25 08:14:41 +00:00
George Rimar 1a4f89ab0a [ELF] - Removed dead declarations. NFC.
llvm-svn: 267381
2016-04-25 08:08:54 +00:00
Peter Collingbourne eb4d823184 Add a note to the test explaining why it doesn't match gold's behaviour.
llvm-svn: 267371
2016-04-25 00:19:47 +00:00
Davide Italiano bfccefd514 [ELF] Reinstate 'else' which was previously removed.
It turns out it's actually needed.

llvm-svn: 267358
2016-04-24 18:23:21 +00:00
Davide Italiano 7d32a4d27f [ELF] Simplify. Remove unneeded else. NFC.
llvm-svn: 267333
2016-04-24 07:19:32 +00:00
Simon Atanasyan 9cf3bf659c [ELF][MIPS] Add test case to check creation of GOT entries for weak symbols. NFC
llvm-svn: 267327
2016-04-24 05:08:43 +00:00
Peter Collingbourne dbe4187d11 ELF: Simplify preemption logic. Do not include weak undefined symbols in non-DSOs.
Add a test for -Bsymbolic + undefined symbols.

llvm-svn: 267323
2016-04-24 04:29:59 +00:00
Peter Collingbourne 7fa5970e69 Test what I intended to test.
llvm-svn: 267316
2016-04-24 02:42:34 +00:00
Peter Collingbourne 6d01a35ef6 ELF: Forbid undefined symbols with non-default visibility in DSOs.
llvm-svn: 267315
2016-04-24 02:31:04 +00:00
Peter Collingbourne d869a040ee ELF: Always include undefined DSO symbols in the symbol table.
Fixes check-llvm when bootstrapping.

Also remove mostly dead and most likely incorrect logic regarding preemption
of weak undefined symbols.

llvm-svn: 267314
2016-04-24 02:31:02 +00:00
Davide Italiano ae153ec4b4 [ELF] Use llvm-mc rather than checking in a file.
Now that the support for the 'new' relocations is available.

llvm-svn: 267310
2016-04-24 01:56:02 +00:00
Rui Ueyama 55274e3fcb Add a file comment about the Ulrich's document and don't repeat it in other comments.
llvm-svn: 267261
2016-04-23 01:10:15 +00:00
Rui Ueyama 209f6cb055 Add more comment.
llvm-svn: 267260
2016-04-23 01:10:13 +00:00
Rui Ueyama 4255475139 Add comments.
llvm-svn: 267259
2016-04-23 00:26:32 +00:00
Rui Ueyama 9c1112d09a Use ScriptParserBase features to parse linker script expressions.
Previously, we have re-implemented utility functions such as `expect`
or `next` in LinkerScript.cpp. This patch reuses the existing
implementation that is in ScriptParser.cpp.

llvm-svn: 267255
2016-04-23 00:04:03 +00:00
Rui Ueyama 4a46539c24 Devirtualize ScriptParserBase. NFC.
ScriptParserBase class is a container of collection of various methods
to parse linker script-ish text. It had a virtual method `run` to run
the parser. But we don't have to enforce its descendents to implement
that. It's up to them.

This patch removes pure virtual function `run`.

llvm-svn: 267246
2016-04-22 22:59:24 +00:00
Rui Ueyama e12fd0fc2c Fix link failure.
llvm-svn: 267245
2016-04-22 22:59:22 +00:00
Rafael Espindola 0b9531c8e6 Bring r267164 back with a fix.
The fix is to handle local symbols referring to SHF_MERGE sections.

Original message:

GC entries of SHF_MERGE sections.

It is a fairly direct extension of the gc algorithm. For merge sections
instead of remembering just a live bit, we remember which offsets
were used.

This reduces the .rodata sections in chromium from 9648861 to 9477472
bytes.

llvm-svn: 267233
2016-04-22 22:09:35 +00:00
Rui Ueyama 1e9e615f92 LTO: Merge -lto-no-discard-value-names with -save-temps.
This patch is to remove -lto-no-discard-value-names flag and
instead to use -save-temps as we discussed in the post-commit
review thread for r267020.

Differential Revision: http://reviews.llvm.org/D19437

llvm-svn: 267230
2016-04-22 21:43:10 +00:00
Rui Ueyama b29465fe47 Remove unused #include.
llvm-svn: 267222
2016-04-22 21:17:55 +00:00
Rui Ueyama 412c802bda Move BitcodeCompiler constructor to the .cpp file. NFC.
llvm-svn: 267221
2016-04-22 21:16:18 +00:00
Rui Ueyama 5fa60985cf Inline getInteger as it's too short to be a function. NFC.
llvm-svn: 267219
2016-04-22 21:05:04 +00:00
Rui Ueyama e29a975d23 Update a comment for r267145.
llvm-svn: 267218
2016-04-22 21:02:27 +00:00
Rui Ueyama 0b3868ec6b Move uintX_t typedef to the class definition. NFC.
Now it is doable because LinkerScript is a template class.

llvm-svn: 267212
2016-04-22 20:41:07 +00:00
Peter Collingbourne 66ac1d6152 ELF: Implement basic support for --version-script.
This patch only implements support for version scripts of the form:
  { [ global: symbol1; symbol2; [...]; symbolN; ] local: *; };
No wildcards are supported, other than for the local entry. Symbol versioning
is also not supported.

It works by introducing a new Symbol flag which tracks whether a symbol
appears in the global section of a version script.

This patch also simplifies the logic in SymbolBody::isPreemptible(), and
teaches it to handle the case where symbols with default visibility in DSOs
do not appear in the dynamic symbol table because of a version script.

Fixes PR27482.

Differential Revision: http://reviews.llvm.org/D19430

llvm-svn: 267208
2016-04-22 20:21:26 +00:00
Rafael Espindola e2eb5f837b Update test.
Sorry about the noise.

llvm-svn: 267207
2016-04-22 20:21:25 +00:00
Rafael Espindola 55a1d50b3a Add missing options that were required to crash.
llvm-svn: 267204
2016-04-22 20:07:59 +00:00
Rafael Espindola e7809c3a28 Add a reduction of the recent bootstrap failure.
llvm-svn: 267202
2016-04-22 20:05:16 +00:00
Rui Ueyama 630a382ba1 Reorganize LinkerDriver::link and add comments. NFC.
llvm-svn: 267201
2016-04-22 19:58:47 +00:00
Peter Collingbourne e8d466293a Update an out of date comment.
llvm-svn: 267200
2016-04-22 19:56:45 +00:00
Rui Ueyama 8bf71066c5 Inline SymbolTable::compareCommons and add comments. NFC.
llvm-svn: 267195
2016-04-22 19:34:59 +00:00
Rafael Espindola 46c039f2c0 Revert "GC entries of SHF_MERGE sections."
This reverts commit r267164.

    Revert "Trying to fix the windows build."

    This reverts commit r267168.

Debugging a bootstrap problem.

llvm-svn: 267194
2016-04-22 19:31:35 +00:00
Peter Collingbourne 3a35c4546d ELF: Scan for undefined symbols in shlibs and symbols in dynamic lists before LTO.
This ensures that these features work correctly with bitcode files.

llvm-svn: 267188
2016-04-22 18:47:52 +00:00
Peter Collingbourne 760e583e22 ELF: Implement --export-dynamic-symbol.
llvm-svn: 267184
2016-04-22 18:44:06 +00:00
Peter Collingbourne dadcc17ead ELF: Move Visibility, IsUsedInRegularObj and MustBeInDynSym flags to Symbol.
These are properties of a symbol name, rather than a particular instance
of a symbol in an object file. We can simplify the code by collecting these
properties in Symbol.

The MustBeInDynSym flag has been renamed ExportDynamic, as its semantics
have been changed to be the same as those of --dynamic-list and
--export-dynamic-symbol, which do not cause hidden symbols to be exported.

Differential Revision: http://reviews.llvm.org/D19400

llvm-svn: 267183
2016-04-22 18:42:48 +00:00
Davide Italiano 9f8efffe29 [LTO] Create Undefined Bitcode symbol when we drop a comdat member.
Differential Revision:  http://reviews.llvm.org/D19389

llvm-svn: 267181
2016-04-22 18:26:33 +00:00
Rafael Espindola a630380a0c Trying to fix the windows build.
llvm-svn: 267168
2016-04-22 17:10:28 +00:00
Rafael Espindola caa831d85a GC entries of SHF_MERGE sections.
It is a fairly direct extension of the gc algorithm. For merge sections
instead of remembering just a live bit, we remember which offsets were
used.

This reduces the .rodata sections in chromium from 9648861 to 9477472
bytes.

llvm-svn: 267164
2016-04-22 16:46:08 +00:00
Rafael Espindola 197d6a882f This reverts commit r267154 and r267161.
It turns out that this will read data from the section to properly
handle Elf_Rel implicit addends.

Sorry for the noise.

Original messages:

Try to fix Windows lld build.

Move getRelocTarget to ObjectFile.
It doesn't use anything from the InputSection.

llvm-svn: 267163
2016-04-22 16:39:59 +00:00
Nico Weber 104871f433 Try to fix Windows lld build.
llvm\tools\lld\ELF\MarkLive.cpp(49): error C2872: 'ObjectFile': ambiguous symbol
llvm\tools\lld\elf\InputFiles.h(100): note: could be 'lld:🧝:ObjectFile'
llvm\include\llvm/Object/IRObjectFile.h(26): note: or       'llvm::object::ObjectFile'
llvm\tools\lld\ELF\MarkLive.cpp(133): note: see reference to function template instantiation
    'void forEachSuccessor<ELFT>(lld:🧝:InputSection<ELFT> *,
                                 std::function<void (lld:🧝:InputSectionBase<ELFT> *)>)'
    being compiled with
                [ ELFT=llvm::object::ELF32LE ]
llvm\tools\lld\ELF\MarkLive.cpp(136): note: see reference to function template instantiation
    'void lld:🧝:markLive<llvm::object::ELF32LE>(lld:🧝:SymbolTable<llvm::object::ELF32LE> *)
    being compiled

llvm-svn: 267161
2016-04-22 15:23:02 +00:00
Rafael Espindola ea4d177977 Move getRelocTarget to ObjectFile.
It doesn't use anything from the InputSection.

llvm-svn: 267154
2016-04-22 14:17:14 +00:00
Rafael Espindola 5221516a04 Simplify. NFC.
llvm-svn: 267147
2016-04-22 11:46:28 +00:00
George Rimar dffc1410c5 [ELF] - Implemented linkerscript ALIGN command
ALIGN(exp)
Return the location counter (.) aligned to the next exp boundary. (https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/4/html/Using_ld_the_GNU_Linker/expressions.html)

Patch implements this command.
This fixes PR27406.

Differential revision: http://reviews.llvm.org/D19364

llvm-svn: 267145
2016-04-22 11:40:53 +00:00
George Rimar fba45c41df Recommitted r267132 "[ELF] - implemented ternary operator for linkerscript expressions"
With fix: removed redundant Dot parameter.

Original commit message:
[ELF] - implemented ternary operator for linkerscript expressions

Patch implements ternary operator for linkerscript expressions.
Like:

SECTIONS {
 . = 0x1 ? 0x2 : 0x3;
...
}

Differential revision: http://reviews.llvm.org/D19332

llvm-svn: 267140
2016-04-22 11:28:54 +00:00
George Rimar f8e230b277 Revert r267132 as it broke buildbot.
llvm-svn: 267134
2016-04-22 10:51:34 +00:00
George Rimar 8c4acddebc [ELF] - implemented ternary operator for linkerscript expressions
Patch implements ternary operator for linkerscript expressions.
Like:

SECTIONS {
 . = 0x1 ? 0x2 : 0x3;
...
}

Differential revision: http://reviews.llvm.org/D19332

llvm-svn: 267132
2016-04-22 10:35:34 +00:00
Rui Ueyama c9f402eadc Inline SectionRule::match.
This short function was used only once and didn't provide much value.

llvm-svn: 267086
2016-04-22 00:23:52 +00:00
Rui Ueyama c998a8c044 ELF: Make the special variable "." as a LinkerScript class member.
I will eventually make `evaluate` function a usual parse function
rather than a function that works on a separate token list.
This is the first step toward that.

llvm-svn: 267083
2016-04-22 00:03:13 +00:00
Rafael Espindola 5be6064974 Don't gc protected symbols.
llvm-svn: 267081
2016-04-21 23:59:19 +00:00
Rui Ueyama 8ec77e64fc ELF: Change how to handle KEEP linker script command.
You can instruct the linker to not discard sections even if they
are unused and --gc-sections option is given. The linker script
command for doing that is KEEP. The syntax is KEEP(foo) where foo
is a section name. KEEP commands are written in SECTIONS command,
so you can specify the order of sections *and* which sections
will be kept.

Each sub-command in SECTIONS command are translated into SectionRule
object. Previously, each SectionRule has `Keep` bit. However,
if you think about it, this hid information in too deep in elements
of a list. Semantically, KEEP commands aren't really related to
SECTIONS subcommands. We can keep the section list for KEEP in a
separate list. This patch does that.

llvm-svn: 267065
2016-04-21 22:00:51 +00:00
Rafael Espindola 4d480ed545 Internalize linkonce_odr more often.
Since there is a copy in every translation unit that uses them, they can
be omitted from the symbol table if the address is not significant.

This still doesn't catch as many cases as the gold plugin. The
difference is that we check canBeOmittedFromSymbolTable in each file and
use lazy loading which limits what it can do. Gold checks it in the merged file.

I think the correct way of getting the same results as gold is just to
cache in the IR the result of canBeOmittedFromSymbolTable.

llvm-svn: 267063
2016-04-21 21:44:25 +00:00
Rui Ueyama 467dbdd030 Remove SymPair and instead use two DefinedRegulars instead.
I noticed that I was looking for the definition of SymPair when hacking
the Writer, only to find that it is just a pair of DefinedRegular symbols.
I don't think it provides more values than the cost of using brainpower
to memorize the type. I didn't roll back r266317, which introduced SymPair,
because the patch removes code repetitions. I ported that change to new
code.

llvm-svn: 267047
2016-04-21 20:50:15 +00:00
Rafael Espindola ae605c1b0c Start adding support for internalizing shared libraries.
llvm-svn: 267045
2016-04-21 20:35:25 +00:00
Rui Ueyama c3e2a4b006 ELF: Change the return type of getSectionOrder.
Also changed the function name and added comments.

llvm-svn: 267044
2016-04-21 20:30:00 +00:00
Saleem Abdulrasool 1b5bf445a0 ELF: support -- version of discard-{all,locals}
GNU ld and gold only support the discard-all and discard-locals with two dashes.
Retain the compatibility with the one dash spelling, but also accept the two
dashed form.

llvm-svn: 267032
2016-04-21 18:29:13 +00:00
Saleem Abdulrasool 1761dddc4f ELF: alias `--no-copy-dt-needed-entries` to `--no-add-needed`
`--add-needed` and `--no-add-needed` have been deprecated due to the similarity
of their spelling to `--as-needed` and `--no-as-needed`.  They have been renamed
to `--copy-dt-needed-entries` and `--no-copy-dt-needed-entries`.

llvm-svn: 267031
2016-04-21 18:29:09 +00:00
Davide Italiano 5abcb3cc5b [LTO] Discard names for values that are not global by default.
Rafael reported on the mailing list that this reduces peak memory
usage while linking llvm-as by 15%. It makes sense to make it
the default, and introduce an inverse knob -lto-no-discard-value-names
for those who want to restore the old behavior.

llvm-svn: 267020
2016-04-21 17:46:38 +00:00
Rafael Espindola e26b50e71a Reduce templating. NFC.
llvm-svn: 267018
2016-04-21 17:37:11 +00:00
Rafael Espindola b312a740ae Delete the needsPlt target hook.
It can be made redundant with getRelExpr.

llvm-svn: 267012
2016-04-21 17:30:24 +00:00
Eugene Zelenko a7a55c4d27 Fix builds broken in r267008.
llvm-svn: 267010
2016-04-21 17:27:04 +00:00
Eugene Zelenko 1a299eab32 Fix Clang-tidy misc-unused-using-decls and Include What You Use warnings.
Differential revision: http://reviews.llvm.org/D19348

llvm-svn: 267008
2016-04-21 17:14:10 +00:00
Davide Italiano 58f02d0644 [LTO] An interesting case which shows up how we handle common symbols.
The gold plugin logic for common symbols is a little bit convoluted
as the plugin API has not an explicit way to update the alignment.
In gold, then, we need to keep the bitcode symbol @a around because
that's the only way to get the alignment right in the final object.

In lld, this is not true. We already have all the informations we
need about common symbols (size/alignment) so we don't have to
keep the existing symbol and pass it to the mover.

llvm-svn: 267007
2016-04-21 17:11:39 +00:00
Rafael Espindola 34b335bdf7 Don't recompute getRelExpr. NFC.
llvm-svn: 267005
2016-04-21 16:59:25 +00:00
Rafael Espindola 0c869a752e Moves needsPlt to Writer.cpp.
It was only used there.

llvm-svn: 267002
2016-04-21 16:57:32 +00:00
Rafael Espindola 543bebd8ee Fix test to run everywhere.
Because of X86 instead of x86 is was masked as unsupported everywhere.

llvm-svn: 266996
2016-04-21 15:51:28 +00:00
Rafael Espindola 29af472cf6 Use llvm::CachedHash.
llvm-svn: 266982
2016-04-21 12:21:06 +00:00
George Rimar 72ab8481fa [ELF] - Make LinkerScript::getSectionOrder private. NFC.
llvm-svn: 266979
2016-04-21 11:28:11 +00:00
George Rimar dbbd8b15bf [ELF] - Use ArrayRef instead of std::vector& for LinkerScript module. NFC.
llvm-svn: 266978
2016-04-21 11:21:48 +00:00
George Rimar 71b26e94fd [ELF] - Get rid of SectionOrder array.
SectionOrder vector was a part of LinkerScript class.

It can be removed because Commands vector contains the 
same information and SectiorOrder is just a subset.

Differential revision: http://reviews.llvm.org/D19171

llvm-svn: 266974
2016-04-21 10:22:02 +00:00
Davide Italiano 253f71ba5a [LTO/Test] Make x86_64-darwin bot happy again.
llvm-svn: 266957
2016-04-21 05:30:32 +00:00
Davide Italiano afd1b06d8e [LTO] Another couple of tests for cases we already get right.
-> Drop linkage when converting to decl
-> Handling of unnamed_addr.

llvm-svn: 266954
2016-04-21 04:50:08 +00:00
Davide Italiano 3c0410d09d [LTO] Discard names for Values that are not global.
This is not on by default (but it might be in the future).
The knob to enable the optimization is -lto-discard-value-names.

llvm-svn: 266953
2016-04-21 04:46:22 +00:00
Nico Weber 984cd3535d Reland test change.
llvm-svn: 266943
2016-04-21 01:33:04 +00:00
Nico Weber a7a848f10d Revert unintentionally commited bits in r266935.
llvm-svn: 266942
2016-04-21 01:31:37 +00:00
Nico Weber 848334704d unbreak COFF/out.test after r266929
llvm-svn: 266935
2016-04-20 23:30:14 +00:00
Nico Weber 5660de7877 lld-link: Fix default output name with /dll flag.
If /dll is passed, the default output filename should be foo.dll,
not foo.exe.
http://reviews.llvm.org/D19321

llvm-svn: 266929
2016-04-20 22:34:15 +00:00
Simon Atanasyan 98a4ba54df [ELF][MIPS] Treat R_MIPS_TLS_{D}TPREL_HI16/LO16 as relative relocations
These relocations are calculated as S + A - DTPREL or S + A - TPREL,
where DTPREL = TlsVA - 0x8000, TPREL = TlsVA - 0x7000. So the result
is relative to the TLS output section and is not an absolut value
The fix allows to escape creation of unnecessary dynamic relocations
in case of DSO linking.

llvm-svn: 266923
2016-04-20 21:57:51 +00:00
Simon Atanasyan ca58a8ff5b [ELF][MIPS] Create GOT entries for R_MIPS_REL32 dynamic relocations
MIPS ABI turns using of GOT and dynamic relocations inside out. While
regular ABI uses dynamic relocations to fill up GOT entries MIPS ABI
requires dynamic linker to fills up GOT entries using specially sorted
dynamic symbol table. This affects even dynamic relocations against
symbols which do not require GOT entries creation explicitly, i.e. do
not have any GOT-relocations. So if a preemptible symbol has a dynamic
relocation we anyway have to create a GOT entry for it.

If a non-preemptible symbol has a dynamic relocation against it, dynamic
linker takes it st_value, adds offset and writes down result of the
dynamic relocation. In case of preemptible symbol dynamic linker
performs symbol resolution, writes the symbol value to the GOT entry and
reads the GOT entry when it needs to perform a dynamic relocation.

Differential Revision: http://reviews.llvm.org/D18948

llvm-svn: 266921
2016-04-20 21:40:33 +00:00
Kevin Enderby dd98c91e08 Needed change to lld for the change to libObject’s getName() for symbols now returning Expected<...>
With the llvm change in r266919 this is the matching needed change to the lld code
now that libObject’s getName() for symbols now returning Expected<...> .

llvm-svn: 266920
2016-04-20 21:24:51 +00:00
Rui Ueyama 6011811beb Define and use a utility function. NFC.
llvm-svn: 266914
2016-04-20 20:54:13 +00:00
Rui Ueyama 99e519cdeb ELF: Redefine parseExpr to parse an expression. NFC.
Previously the function reads an operator and the rest of
the expressions. This patch makes it to actually parse an expression
which starts with a primary pexression followed by other expressions
concatenated with operators.

llvm-svn: 266912
2016-04-20 20:48:25 +00:00
Rui Ueyama 07320e4030 ELF: Template LinkerScript class.
Originally, linker scripts were basically an alternative way to specify
options to the command line options. But as we add more features to hanlde
symbols and sections, many member functions needed to be templated.
Now most the members are templated. It is probably time to template the
entire class.

Previously, LinkerScript is an executor of the linker script as well as
a storage of linker script configurations. This is not suitable to template
the class because when we are reading linker script files, we don't know
the ELF type yet, so we can't instantiate ELF-templated classes.

In this patch, I defined a new class, ScriptConfiguration, to store
linker script configurations. ScriptParser writes parse results to it,
and LinkerScript uses them.

Differential Revision: http://reviews.llvm.org/D19302

llvm-svn: 266908
2016-04-20 20:13:41 +00:00
Davide Italiano bcc7f617cd [LTO] Another type merge test.
llvm-svn: 266899
2016-04-20 18:38:09 +00:00
Davide Italiano a479b968e9 [LTO] Add a test to ensure we handle basic type merging correctly.
llvm-svn: 266896
2016-04-20 18:10:25 +00:00
Rafael Espindola c6b17bdc29 Delete refersToGotEntry.
It can be computed from the expression.

llvm-svn: 266890
2016-04-20 17:30:22 +00:00
Rafael Espindola 475dbf42e4 Simplify mips gp0 handling.
In all currently supported cases this is a nop.

llvm-svn: 266888
2016-04-20 17:20:49 +00:00
Rafael Espindola 2081dbcc7a Inline canRelaxTls.
It was always called in a position where the relocation type was already
known.

llvm-svn: 266880
2016-04-20 15:01:42 +00:00
Rafael Espindola f54413c18e Simplify canRelaxTls.
Check isTls in the called and pass a SymbolBody&.

llvm-svn: 266879
2016-04-20 14:52:18 +00:00
Rafael Espindola cc36a63f0b Move canRelaxTls to Writer.cpp. NFC.
llvm-svn: 266878
2016-04-20 14:41:55 +00:00
Rafael Espindola 6eda85ac1f Delete needsDynRelative.
It is now redundant. Writer.cpp can reason that 2 dynamic relocations
are needed: one to find the final got entry address and one to fill the
got entry.

llvm-svn: 266876
2016-04-20 14:36:24 +00:00
Sean Silva 580c1b6952 Revert "[ELF] - Avoid using memset for zero-initialization of struct member. NFC."
This reverts commit r266618. It breaks basically everything.

I think VS2013 doesn't interpret this code in the same way.
The size field (at least) is left uninitialized, causing all sorts of havok
(e.g. creating a 34GB file for a trivial hello world program).

The offending compiler reports itself as follows:

    c:\release-vs2013>cl /?
    Microsoft (R) C/C++ Optimizing Compiler Version 18.00.40629 for x64
    Copyright (C) Microsoft Corporation.  All rights reserved.

llvm-svn: 266857
2016-04-20 04:26:16 +00:00
Rafael Espindola 58cd5db4ef Simplify mips got handling.
This avoids computing the address of a position in the got just to then
subtract got->getva().

llvm-svn: 266831
2016-04-19 22:46:03 +00:00
Rafael Espindola bf7ca7eb5b Document how a binary file was created.
llvm-svn: 266819
2016-04-19 20:52:28 +00:00
Rui Ueyama 0536ec0242 Make a function file-scoped.
llvm-svn: 266816
2016-04-19 20:50:25 +00:00
Rafael Espindola f350d25942 Fix pr27420.
Return the right expression for R_X86_64_GOTPCRELX and
R_X86_64_REX_GOTPCRELX.

llvm-svn: 266810
2016-04-19 20:18:52 +00:00
Rui Ueyama 7a81d674f6 Attempt to fix buildbot.
llvm-svn: 266799
2016-04-19 19:04:03 +00:00
Rui Ueyama 960504b91d ELF: Add +, -, *, / and & to SECTIONS linker script command.
This patch is based heavily on George Rimor's patch
http://reviews.llvm.org/D19221.

In the linker script, you can write expressions to compute addresses.
Currently we only support "+" operator. This adds a few more operators.

Since this patch adds * and /, we need to handle operator precedences
properly. I implemented that using the operator-precedence grammar.

Differential Revision: http://reviews.llvm.org/D19237

llvm-svn: 266798
2016-04-19 18:58:11 +00:00
George Rimar a3ab1091d1 Updated comment. NFC.
llvm-svn: 266727
2016-04-19 12:09:25 +00:00
Duncan P. N. Exon Smith 28d8d04657 LTO: Adapt to LLVM API changes in r266713
llvm-svn: 266714
2016-04-19 04:57:40 +00:00
Rui Ueyama afb1901e42 COFF: Support /manifestinput command line option.
Manifest file is a separate or embedded XML file having metadata
of an executable. As it is XML, it can contain various types of
information. Probably the most popular one is to request escalated
priviledges.

Usually the linker creates an XML file and embed that file into
an executable. However, there's a way to supply an XML file from
command line. /manifestniput is it.

Apparently it is over-designed here, but if you supply two or more
manifest files, then the linker needs to merge the files into a
single XML file. A good news is that we don't need to do that ourselves.
MT.exe command can do that, so we call the command from the linker
in this patch.

llvm-svn: 266704
2016-04-19 01:21:58 +00:00
Rui Ueyama 9e957a0ac6 Rename LocationNode -> SectionsCommand.
They are called sections-command in the doc, so it is nice to keep
it consistent with it.
https://sourceware.org/binutils/docs/ld/SECTIONS.html#SECTIONS

llvm-svn: 266668
2016-04-18 21:00:45 +00:00
Rui Ueyama 54115af45e Remove redundant curly braces.
llvm-svn: 266667
2016-04-18 21:00:43 +00:00
Rui Ueyama 7c18c28c97 Refactor LinkerScript::assignAddresses. NFC.
llvm-svn: 266666
2016-04-18 21:00:40 +00:00
Rafael Espindola de088e69a1 Add missing dependency.
llvm-svn: 266655
2016-04-18 19:03:36 +00:00
George Rimar 4f2aa57569 [ELF] - Avoid using memset for zero-initialization of struct member. NFC.
llvm-svn: 266618
2016-04-18 15:16:17 +00:00
Rafael Espindola f4c1cd4006 Fix handling of R_X86_64_GOT32.
It computes the offset to the end of .got.

llvm-svn: 266610
2016-04-18 12:58:59 +00:00
Rafael Espindola ece62b962e Simplify handling of R_X86_64_TPOFF32. NFC.
llvm-svn: 266609
2016-04-18 12:44:33 +00:00
Rafael Espindola 5bf59728e2 Remove isGotRelative.
It is now redundant with the expression. While at it, handle both "X -
Got" and "Got - PC".

llvm-svn: 266607
2016-04-18 12:31:37 +00:00
Rafael Espindola 3f5d634c73 Have getRelExpr handle all cases on x86.
This requires adding a few more expression types, but is already a small
simplification. Having Writer.cpp know the exact expression will also
allow further simplifications.

llvm-svn: 266604
2016-04-18 12:07:13 +00:00
Rafael Espindola 3c20fb4e5d Merge duplicated cases. NFC.
llvm-svn: 266601
2016-04-18 11:53:42 +00:00
Mehdi Amini de3f7678d1 Add missing header (NFC)
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266597
2016-04-18 09:33:41 +00:00
Mehdi Amini 0bc6b2b5a0 Add missing header (NFC)
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266596
2016-04-18 09:26:29 +00:00
Rafael Espindola 99c224787b Delete the now redundant pointsToLocalDynamicGotEntry.
llvm-svn: 266584
2016-04-18 01:34:20 +00:00
Rafael Espindola df17277d72 Have getRelExpr return the final values for tls gd.
llvm-svn: 266583
2016-04-18 01:29:15 +00:00
Rafael Espindola c4d56970dc Change getRelExpr to return the final value for TLSLD. NFC.
llvm-svn: 266580
2016-04-18 00:28:57 +00:00
Rafael Espindola abf6c650ac Make CreateTargetMachine as small as possible.
It is a pity that we have to create a TargetMachine once per thread,
so at least make that code as small as possible.

llvm-svn: 266578
2016-04-17 23:20:08 +00:00
Ismail Donmez 23e5a38407 Fix shared build after r266484
llvm-svn: 266558
2016-04-17 09:01:51 +00:00
Duncan P. N. Exon Smith 2c66b23d79 LTO: Merge debug info types when linking bitcode
Make sure lld enables ODR type uniquing for debug info when invoking
LTO, as a follow-up to LLVM r266549.

llvm-svn: 266555
2016-04-17 07:35:38 +00:00
Simon Atanasyan b5c0025d1d Remove links to deleted TODOs.
llvm-svn: 266528
2016-04-16 11:11:56 +00:00
Simon Atanasyan 737a92c893 [ELF] Include Twine.h header to restore LLD build after r266524. NFC
llvm-svn: 266527
2016-04-16 10:58:45 +00:00
George Rimar 652852c5c0 Recommitted 266457 with fix:
* Do script driven layout only if SECTIONS section exist.

Initial commit message:

[ELF] - Implemented basic location counter support.

This patch implements location counter support. 
It also separates assign addresses for sections to assignAddressesScript() if it scipt exists.

Main testcase is test/ELF/linkerscript-locationcounter.s, It contains some work with location counter. It is basic now.
Implemented location counter assignment and '+' operations.

Patch by myself with LOTS of comments and design suggestions from Rui Ueyama.

Differential revision: http://reviews.llvm.org/D18499

llvm-svn: 266526
2016-04-16 10:10:32 +00:00
Alex Denisov bb241249df Replace hardcoded comment at 'lit.site.cfg.in'
At the moment almost every lit.site.cfg.in contains two lines comment:

  ## Autogenerated by LLVM/Clang configuration.
  # Do not edit!

The patch adds variable LIT_SITE_CFG_IN_HEADER, that is replaced from
configure_lit_site_cfg with the note and some useful information.

llvm-svn: 266521
2016-04-16 07:09:39 +00:00
Davide Italiano 493b683f79 [LTO] Don't crash on a BitcodeFile without DataLayout.
Emit an error instead.

llvm-svn: 266504
2016-04-16 01:33:33 +00:00
Davide Italiano 0ce90908e0 [LTO] Add datalayout to test to prevent an assertion in Debug mode.
While here, run this test only on x86.

llvm-svn: 266487
2016-04-15 22:58:57 +00:00
Rui Ueyama faac567e68 Revert r266457: "[ELF] - Implemented basic location counter support."
This reverts commit r266457 as it breaks "hello world" both on
Linux and FreeBSD.

llvm-svn: 266485
2016-04-15 22:39:27 +00:00
Davide Italiano bc176631cd [LTO] Implement parallel Codegen for LTO using splitCodeGen.
Parallelism level can be chosen using the new --lto-jobs=K option
where K is the number of threads used for CodeGen. It currently
defaults to 1.

llvm-svn: 266484
2016-04-15 22:38:10 +00:00
Rafael Espindola 5628ee7631 Simplify got handling.
Each getRelExpr is now expected to return the correct got expression
instead of having Writer patch it up with needsGot.

llvm-svn: 266466
2016-04-15 19:14:18 +00:00